Given:
-(5z + 12) = 18
First Step:
Use distributive property and expand the parenthesis.
Also distribute the negative symbol
-5z + (-12) = 18
-5z - 12 = 18
Second Step:
Add 12 to both sides of the equation.
-5z - 12 + 12 = 18 + 12
-5z = 30
Third Step:
Divide both sides by -5
[tex]\begin{gathered} \frac{-5z}{-5}=\frac{30}{-5} \\ \\ z\text{ = -6} \end{gathered}[/tex]ANSWER:
z = -6